ALASKAN GLACIER STUDIES
destruction of a well-beaten path, which formerly followed the edge of the river bank for some distance. Shrubs formerly inside this path were everywhere falling over the edge of the undercut river bank in 1910. About the middle of August, when the waves were not as powerful as they had been
FIG. 59. CHTLDS GIACEBB IN 1909 AND 1910. Note the tongue of ice on the north edge, threatening the railroad bridge, in 1910.
earlier in the Hummer, the largest ice fall, or "slough," which we saw sent a wave across the river with lightning rapidity, causing the water to wash up over the 15 to 20 foot bank near where we stood and to extend back a short distance into the forest. The wave, of course, rose highest directly opposite the ice fall, its height on the bank decreasing both up- and down-stream. Six or seven ring waves in succession splashed far up the river bank, the first one visibly running up-stream, against an eight or nine-mile-an-hour cur-